The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 15, 1990
Filed:
Oct. 17, 1988
Applicant:
Inventors:
Assignee:
Ricoh Company, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01S / ;
U.S. Cl.
CPC ...
372 50 ; 372 38 ; 372 29 ; 357 74 ; 357 19 ; 357 75 ; 357 80 ;
Abstract
A semiconductor laser unit includes a casing, a printed circuit board fastened to the casing, and a laser diode unit which includes a laser diode and a photodiode for monitoring a laser beam emitted from the laser diode. The laser diode unit is accommodated in the casing. The semiconductor laser unit also includes a monitor output amplifier for amplifying an output signal of the photodiode, and a reference voltage generator for generating a reference voltage signal which is to be compared with an output voltage signal of the monitor output amplifying means in order to set a light intensity of the laser beam to a predetermined value.